Wireless telegraphy.



No. 808,641. PATENTED JAN. 2, 1906.

P. B. DELANY.

WIRELESS TELEGRAPHY.

APPLICATION FILED MAY 14,1903.

ENTTED STATES PATENT OFFICE.

WIRELESS TELEGRAPHY.

Specification of Letters Patent Patented Jan. 2, 1906.

Application filed May 14,1903- Serial No. 167,137.

To all whom it may concern.-

Be it known that I, PATRICK B. DELANY, a citizen of the United States,residing in South Orange, county of Essex, State of New Jersey,

.have invented certain new and useful Improvements in WirelessTelegraphy, of which the following is a specification.

This invention relates to the reception of electrical or electromagneticwaves, impulses, or oscillations, however transmitted, from a distantstation, for the conveyance of signals. To this end the inventioncontemplates the use of a contact automatically maintained by localcontrol, with rapidly-recurring variations or degrees of pressure, andthrough which the received oscillations pass to earth, with the effectof more or less modifying or varying the same, and being thereby mademanifest in an appropriate receiver apparatus. Such a variable contactmight be termed a microphonic or floating con"- tact; and it may be saidthat the received waves or impulses act disruptively thereon,

and are, for that reason, made manifest in the telephone or otherreceiver. So far as is known, this mode of reception is new and themanner in which it may be utilized may be varied without departing fromthe princile ofoperation. Experience has demonstrated that this newsystem of reception affords radically improved results in the certainty,sharpness, or definition of the re ceived signals.

In the accompanying drawings: Figure 1 is a diagram illustrating theinvention; Fig. 2 shows the use of a siphon-recorder as a receiver; and,Fig. 3 shows a cable-receiver coil controlling a relay which may controlany kind of a receiver or effect retransmission into another circuit.

a is a relay, preferably polarized, the armature-lever b of which isslightly biased toward the spacing side, i. e., toward the adjustablestop 0.

lb is a local battery included with an adjustable resistance (1 andchoke-coil e in circuit with the winding of the relay and wire f. Abranch 9 from this local circuit of the battery Z?) is connected to thearmature-lever b, and another branch h, to the active adjustable stop i,against which the armature-lever bears with locally-producedrapidly-recurring variation of contact or pressure. From the stop i,extends also a circuit connection j, which contains a choke-coil 76, anadjustable resistance Z and choke-coil m, and then conance Z.

nects with wire g. The receiver at, here shown as a telephone is placedin shunt in series with a condenser 0, around the adjustable resist- Ashunt around the condenser contains a switch 10, by which the condensermay be shunted from the circuit when desired, for instance when someother style of receiver is employed. The vertical conductor g of thereceiver is connected to the stop '5; and therelay-armature is connectedto earth by the ground-tap r. The stop a is shown as carrying a block ofyielding material s, as felt or rubber which at all times maintains amore or less perfect contact between the lever and the contact-post i.

The circuit of the relay is closed through Wire f, relay-winding,adjustable resistance (1, choke-coil e and local battery lb, thedirection of current bein such as to draw the armature-lever b agamstthe stop 11. When this connection is made there is established aroundthe relay-winding a shunt, which may be traced from contact-post 1',through Wire h, to one side of relay, and from armature-lever b by wire9 to the other side of relay. The eifect of this shunt is to producerapid, minute vibrations of the lever 12, resulting in variations ofcontact or pressure between the contact-post 'i and armature-1ever.

The circuit containing the telephone is divided, there being one derivedor shunt circuit from the lever b and wire g, throu h winding of relayto wire it; and another irect from armature-lever I), throughcontactstop i to wire 3'. When, therefore, the lever b is normally drawnagainst i with a variable energy, changes in which occur with highfrequency; the receiver n, will be short-circuited (or sufficiently orsubstantially so) from the battery-circuit. If however, the contactbetween i and b, is modified, or materially raised in resistance by theeifect, disruptive or otherwise, produced by received signal impulses,such local-battery current will then flow through the receiver so as tomake the received signal manifest. The received impulses or oscillationspass by vertical conductor g, contact '5, lever b, and wires g, 1' to,ground. The choke-coil e is placed in the ocal-battery circuit to forcethe oscillations through contact 1', b, and wires g, r, to earth,andprevent them from passing, to any objectionable extent, by wires h,f, and thence to earth at E. The choke-coils 7c, m, are also used toprevent di version of received impulses. By adjusting the resistance clso as to afford sufficient current in the circuit, or by mechanicallyadjusting the relay, the contact between i and b may be maintained ininfinitesimal automatic vibration with substantial uniformity, so thatsuch variations thereof as do occur are not particularly noticeable, ifat all, when listening at the telephone. When the apparatus is soadjusted a most favorable condition for reception exists. magnetic wavesor oscillations pass by wire 9, through the contacts L, 6, to earth atE, there is a change or modification of, or a dis ruptive effect upon,the contacts that 're sults in such variation of current in the circuitincluding the receiver-telephone n, as to cause the signals to becomedistinctly audible therein. The relay, which, as stated, is preferablypolarized, should be quick-acting and have a sensitive balancedarmature. What is commonly knownas the post-office relay of the Britishtelegraph system has been found very satisfactory. The battery orgenerator should be comparatively weak. It has been found that one ortwo wet or dry cells of ordinary type are satisfactory. The adjustableresistance 0 should be such as to afford small variations. Experiencehas shown that a capacity for variation from one ohm upwardly affords asuitable range of adjustment. The relay-armature vibrating or bearingagainst the signal contact-stop i automatically more or less cuts in andout the relay-winding and varies the resistance at the contacts of theshunt containing the re ceiver. The automatic vibrations so produced areof exceedingly small amplitude and high periodicity and may reach inpitch a high musical note, and be susceptible of quite a range ofadjustment affording an unstable microphonic contact of exceedinglightness and delicacy. The effect of the received waves or impulses isto change the resistance at the contact f, b, and consequently changethe note produced in the receiver by the automatic variation of itsshunt at the same time that the relays own shunt is affected.Apparently, the resistance at the contact is raised by eachsignal-impulse received, andthe change in the note caused therebyenables the operator to perceive the dots and dashes with facility. Ithas been found that the best results are obtained by adjusting theresistance (i, so that the note is suppressed, the variations ofpressure at the contacts being not particularly manifest, if at all, inthe telephone. The signal waves or impulses then received apparently actdisruptively upon the seemingly quiet but still imperfect and varyingcontact, the normal variation of which appears to be so delicate as notto be detected by the ear; and after each disruption, caused by receivedwaves or oscillations, the local current in the coil of If now,electrothe relay causes the armature-lever b to be again attractedagainst contact 'i, with considerable force. These variations, changes,

or modifications of the microphonic contact,

produced by the signals, are even and distinct and produce in thetelephone-receiver Well-defined signals. when the automatically variablymaintained microphonic contact is so affected as to raise theresistance, a larger volume of current from the local battery willtraverse the cir: cuit including the telephone-receiver, and, when thereceived waves or impulses pass and the contact returns to normalcondition, the current from the battery is more effectively shunted fromthe receiver. A receiving apparatus having this mode of operation may beused in connection with any organi- Zation of circuits, plain orattuned, and with any combination or disposition of transformers,condensers, or resonance-producing agencies, and, if desired, theautomatically-maintained microphonic contact may be immersed in a fluidor inclosed in a vacuum; or subjected to any of the various subordinateadjunctive agencies or manipulations heretofore proposed for coherers orother delicate contact-receivers.

As indicated in Fig. 2, the telephone-receiver is replaced by theoscillating coil of a cable-receiver operating a siphon-recorder t,making a record upon a traveling tape a.

In Fig. 3, the oscillating cable-coil is shown as controlling the localcircuit of a relay '0, which may appropriately control any kind of areceiving or recording instrument or serve the purpose of retransmissioninto another circuit. v

The elastic cushion s of the instrument a may be omitted, and instead ofa relay, polarized, or otherwise, the instrument may be of anyappropriate character to serve the purpose, or effect the result hereindescribed; and if of such character as to directly make manifest thereceived signals, may itself be the final receiver, thetelephone-receiver n being then omitted.

I claim as my invention 1. In a wireless-telegraph system, a microphoniccontact, in the path of the received waves or impulses, electromagneticmeans, for variably maintaining the microphonic contact at a highperiodicity, comprising a local circuit controlled at said contact, anda receiver whose circuitis controlled at such contact, modification ofthe contactby the received waves or impulses effecting manifestation ofthe signals by the receiver.

2. In a wireless-telegraph system, a receiver comprising the combinationof a relay whose winding is in closed circuit with a battery, ashunt-circuit around the relay-Winding, completed at the contact of therelay, a second shunt-circuit around the relay-winding divided at thesame contact, one division It is apparent that including the localbattery and a resistance, and the other division a receiving instrument.

3. In a wireless-telegraph system, a receiver comprising the combinationofa relay whose winding is in closed circuit with a battery, ashunt-circuit around the relay-winding, including the battery and areceiver which is cut in and out of said shunt-circuit at the contact ofthe relay to which the armature-lever is attracted.

4. In wireless telegraphy, a receiving apparatus comprising a normallymaintained contact constantly varied locally by shunting at a high rateor periodicity, the modification of such contact by received signalwaves or impulses causing a manifestation of the received signals.

5. A system of wireless transmission of signals, comprising a receiverapparatus having a normally maintained path for the received waves oroscillations, means, comprising an electric circuit completed throughsuch path, acting to vary the-latter at a high rate of periodicity, themodification of such path by such waves or oscillations causingmanifestation of the signals.

6. In wireless telegraphy, a receiving apparatus comprising anormallymaintained variable contact, variations of which are automaticallyself-effected at a high rate of periodicity and controlled at saidcontact, through which latter the circuit of a receiver is affected bythe action upon said contact of received signal impulses.

7. In wireless telegraphy, a receiving apparatus comprising a normallymaintained contact, means controlled at such contact for automaticallyrapidly varying it, and a receiving instrument in a circuit controlledby ,said contact which is affected by received signal impulses to makethe latter manifest by the receiver.

8. In wireless telegraphy, a receiving ap paratus comprising a normallymaintained contact, means controlled at such contact for automaticallyelectromagnetically varying it at a high rate of speed, and a receivinginstrument in a circuit controlled at said contact, the contact beingaffected by received signal impulses to thereby make the signalsmanifest in the receiving instrument.

9. In wireless telegraphy, a receivingapparatus comprising a receivinginstrument the circuit of which is divided, one branch thereofcontaining a source of current, and the other not, and a contactautomatically normally maintained and constantly varied by shunting atwhich the branches of the receiver-circuit are controlled and which areso aflected by received signal impulses as to make the latter manifestby the receiving instrument.

10. In wireless telegraphy, a receiving apparatus comprising anelectromagnetic in-' strument having a movable part automaticallymaintained in vibration by variation of its circuit at itscontact-points, a circuit containing a receiver and controlled at saidcontact-points which are affected by received signal impulses so thatthe latter are made manifest by the receiver.

- 11. In wireless telegraphy, a receiving apparatus comprising a partautomatically normally vibrated, normally maintaining a variableelectrical contact and normally producing a continuous sound or note,said variable contact controlling the vibration of the normallyself-vibrated part and being in the path of received signal impulseswhich so affect the contact as to make the signals manifest by changesin the sound or note.

12. In wireless telegraphy, a receiving apparatus comprising a normallymaintained microphonic contact in the path of received oscillations, anelectromagnetic automatic vibrator acting to vary, and controlled bysaid microphonic contact, and an electrical circuit containing areceiver controlled at said contact.

13. In wireless telegraphy, a receiving apparatus comprising a normallymaintained microphonic contact in the path of received oscillationsthrough which contact an undulatory local current is normally passed,means 9 5 for automatically varying said contact and a receiver whoseoperation is controlled at the contact.

14. In wireless telegraphy, a normally maintained contact comprising avibrating TOO member, means controlled by such member and acting to varythe contact at a high rate of periodicity, and a receiving instrument ina circuit controlled by said contact.

In testimony whereof I have hereunto sub- 10 5 scribed my name.

PATRICK B. DELANY.

' Witnesses:

KATHARINE MAGMAHON. WILLIAM A. STAHLIN.

